Deep-sea surprise

The strangeness of deep-sea animals never fails to surprise, and the rare deep-sea 'finger' lobsters are no exception.

Most lobsters have a pair of large, equally (or roughly equally) sized main claws with which they can give a powerful nip! The main claws of 'finger' lobsters, however, are very different — one is quite short and the other remarkably long (sometimes almost as long as the body), with slender fingers lined with comb-like or saw-like rows of sharp spines. The body is about 15–20 cm long, and because they live in the darkness of the deep-sea, they are blind or almost so.

'Finger' lobsters are very difficult to capture, let alone land intact, so any finds are exciting. Recent deep-sea expeditions in the Australasian region captured numbers of these strange lobsters, the deepest at 1767 m.

Our painstaking taxonomic research based on anatomy (morphological analysis) and DNA sequences (molecular analysis) revealed two species new to science. We’ve now formally named them Thaumastocheles bipristis and Thaumastocheles massonktenos. We also found evidence for a third new species of Thaumastocheles from off northern Australia, but we need more specimens in order to complete the scientific work on that one.

Unusual as they are in themselves, 'finger' lobsters are also a specialised branch of the lobster family tree, with a long fossil history as old as the dinosaurs. Thus, each new species discovered helps reveal the bigger picture of the where and why of lobsters.

Discovery is the first step, but we have much more to learn – their burrowing almost certainly helps bring oxygenated water down into the sediments but we know little about their role in the environment, how they earn their living on the deep-sea floor, what they eat and what eats them.

Right now, we are analysing evidence from morphology, molecules and fossils of all lobsters to understand how they have changed through time in both form and diversity resulting in what we see today – we hope to have results to report before long.